Dyeing of acetate artificial silk



Fateznt eol New. MD, 1936 sates zerland, assignors to the firm Society of Chemical Industry in Basle, Basel, Switzerland No Drawing. Original application October 11,

1933, Serial No. 693,219. Divided and this application June 18, 1934, Serial No. 731,216.

Switzerland October 15, 1932 2 Claims.

This application is a division of our application for patent Serial No. 693,219, filed in the United States on October 11, 1933, and in Switzerland on October 15, 1932.

It is known that acetate artificial silk can be dyed by means of feebly basic, sparingly soluble or insoluble dyestuffs. While a large number of such dyestuffs dye acetate artificial silk only feeble or matt tints, the number of dyestuffs capable of dyeing such silk in deep full tints is comparatively small. The number cannot be increased directly by introducing substituents into the molecule of the dyestufi', since very frequently the enlargement of the molecule is associated with a strong diminution of the aflinity of the dyestufi for acetate artificial silk.

The present invention relates to a composition of matter and to a process for dyeing acetate artificial silk in which the dyeing is conducted with a composition of matter consisting of a mixture of a feebly dyeing dyestufi with a similarly constituted dyestufi. The term similarly comprises the homologous, analogous and isomeric dyestuffs having a somewhat similar shade. Such a composition of matter'presents an increased aflinity for the fiber which is quite considerable and makes it possible to use products which hitherto have had no practical value. The dyestufi of low aflinity becomes more readily adsorbed when it is mixed with a dyestufl which in itself has a practically sufficient aflinity for acetate artificial silk. In this manner the affinity of the already. useful acetate artificial silk dyestuff may be improved. Furthermore, it is possible by use of such a composition of matter to shift the color tint of the dyeing in a desired manner in one or the other direction without introduction of substituents into the dyestufi molecule of the dyestuff of good affinity, which introduction, as already stated, may affect the degree of afiinity of the dyestuff in an unfavourable manner.

The compositions of matter of the present invention may be made by adding to the components of a dyestuif during its manufacture a homologue, isomeride or analogue thereof, or by dissolving the finished dyestuffs in a common solvent and precipitating them together in a finely divided state, or by finely grinding together the finished dyestuffs, or by adding the previously finely subdivided dyestuffs to the same dye-bath.

The process is applicable to all classes of dyestuffs usual in the acetate artificial silk dyehouse. It finds a special application in the case 'the temperature of the bath is raised within'% of dyestuif preparations from azo-dyestufls and in the present case from aminoanthraquinones. When the preparation is to be made from an azo-dyestuff there may be added to the coupling component or to the diaZo-component or to both, 5 a homologue, isomeride or analogue thereof, and the mixture of dyestuffs may thus bemade directly, or the finished azo-dyestuffs may be mixed with each other by fine grinding or may be added to the same dye-bath. The procedureis similarin making dyestuff preparations from aminoanthraquinones; in this case a good intermixture may be achieved, among other methods, by dissolving the homologues, isomerides or other analogous dyestuffs in the same solvent and precipitating the mixture in finely divided form in some suitable manner.

The following examples illustrate the invention, the parts being by weight:

Example 1 6 parts of 1-amino-4anilidoanthraquinone and 4 parts of l-amino-4-para-toluidoanthraquinone are introduced into parts of sulfuric acid of 98 per cent. strength at 0-10 C. and the mass is stirred until dissolution is complete. The solution is poured upon ice, filtered and washed until neutral. If the dyestuff thus obtained is brought into a suitable form by grinding with a dispersing agent there is obtained a preparation which dyes acetate artificial silk intensely blue tints, whereas the dyeings obtained with the individual dyestuffs are less intense. The intimate mixture of 1-amino-4-paratoluidoanthraquinone and 1-monomethylamino-4-anilidoanthraquinone also dyes acetate artificial silk blue, as also the ternary mixture of 1-amino-4-anilidoanthra-, quinone, 1-amino-4 para-toluidoanthraquinone and 1-monomethylaminol-anilidoanthraquinone.

Example 2 A greenish blue is obtained by the use of a 55 phenylaminoanthraquinone and 2.5 parts of 1- metholamino 4 (4'-hyd.roxy) -phenylaminoanthraquinone.

What we claim is:

1. A dyeing composition consisting of a mixture of at least two acetate artificial silk dyestufls, of which at least one has a poor afllnity for acetate artificial silk, selected from the group of the products of the general formula i H o N-R,

H H R:

in which R1 stands for a member of the group consisting of hydrogen and methyl, and R2 stands for a member of the group consisting of hydrogen, methyl, hydroxyl and amino.

2. A process of dyeing acetate artificial silk mixture of 7.5 parts of 1-amino-4-(4'-amino)- H H R:

in which R1 stands for a member of the group consisting of hydrogen and methyl, and R2 stands for a member of the group consisting of hydro- 20 gen, methyl, hydroxyl and amino.

FRIEDRICH FELIX. MAX BOMMER.

WILHELM HUBER. 25 

